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arXiv · 0805.1601

Chiral Symmetry of Nucleon Resonances in QCD sum rules

T. Nakamura·P. Gubler·M. Oka
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Abstract

The QCD sum rule approach is employed in order to study chiral properties of positive- and negative-parity nucleon resonances. It is pointed out that nucleons with an ``exotic'' chiral property, which can be represented by local five-quark operators, can be paired with a standard nucleon forming a single chiral multiplet. The sum rules of the five-quark operators, however, are shown not to couple strongly to chirally-``exotic'' nucleon resonances at the mass region of less than 2 GeV.

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T. Nakamura, P. Gubler, M. Oka. 2008-05-12. Chiral Symmetry of Nucleon Resonances in QCD sum rules. https://doi.org/10.1103/physrevd.78.014010

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